Blade-attaching means.



H. KRTIGE R. BLADE ATTAGHING MEANS.

APPLICATION FILED D30. 12, 1908.

' 921,547. Patented May11,1909.

' wF/p/ 707? W/T/VfS'SES HERMANN KRUGER OF HOLZEN, NEAR SGHWERTE, GERMANY.

BLADE-ATTACHING MEANS.

Flo. sewer.

Specification of Letters Patent.

Patented May 11, 1909.

Application filed December 12, 1908. Serial'No. 467,190.

T612 whom it may concern:

has it known that I, HERMANN KRI'ieER, merchant, sub/cot of the German Emperor, resii' et 'Holzen, near Schwerte, in Westphali-a', Empire (if-Germany, have invented new and useful Improvements in or Relating to Blade-Attaching Means, of which the following a specification.

The present invention relates to knives other implements and particularly to table-knives, and an important object is to provide improvml means for attaching knifebl mes the like in metal halts.

Assis known, knife-blades have heretofore been fastened in metal hafts almost exclusively by means of solder or cement. Apart iirom the troublesomeness of securing them in this manner, this mode of attachment has the disadvantages that it always makes the knife very heavy and. when in use the blades frequently gradually become loose.

important object of the invention is to do away with these defects.

Now the present invention is based on the fact that the blade of a knife is not loosened and detached owing to tensions in the blade, but on the contrary owing to the forces which continually recur in use tending to turn the knife-blade around the longitudinal axis of the knife; therefore when providing means for attaching the blade to the haft particular care must be taken that the means of attachment are able to oppose effective resistance to just these forces. With this end in view, in accordance with the present invention the tang is made as a strong, short, slightly tapering pin of optional polygonal, quadrangu ar, triangular,-flat arallelogrammatic, circular, elliptical or ike form, and a strong iplate is attached in the halt at a distance 'rom the upper end of the halt almost equal to the length of the'tang; this plate has in it a hole corresponding in shape exactly or only approximately with the crosssection of the tang, but rather smaller than the end of the tang, so that very great pressure is required to press the wedge-like end 01' a quadrangular tang so far into a quadrangular hole, and still more pressure to press a hexagonal tang for example into the circular hole in the plate in the haft that the bol-- ster of the knife-blade is correctly laced with regard to the haft. Consequent y it is not at all necessary for the shape (of the hole in the plate attached in the haft to corn:- spond' xactly with the shape of theoremsection of the tang, but when the tang is hex- 1 agonal, for example, the hole may very well be circular, and when the tang is a fiat parah lelogram in shape, the hole may be elliptical, and vice versa. In these cases it also depends on the hole in the plate being somewhat too small for the tang to be readily inserted therein. In this manner the strength of the attachment is considerably increased, since the edges of the tang are embedded deeply into the sides of the hole in the plate and become firmly held there, the faces of the hole and tang are deformed and engage one another. I

Owing to a w ed e-shaped tan-g being exceedingly powerfully clamped and simultaneously engaged in the more or less exactly fitting hole in the date, the connection between the haft and b ade is made so firm and secure that it is quite impossible for the blade to be loosened by the normal forces which tend to twist the latter in the bait. But also an exceedingly firm connection between theblade and heft is obtained in an axial direction by means of the tang being compressed firmly in the hole in the plate when. it is driven into the latter, in consequence of the wedge-shaped form of the tang which is rather too large for the hole. In or der to oppose the twisting forces in like mannor, in addition to the above arrangement the bolster of the blade is let into the end of the haft projecting beyond the plate, whcrcby these forces are effectively transmitted from the head of the blade directly to the haft, and it is quite impossible for the tang to bend.

In order that the invention may be clearly understood reference will be made to the accompanying drawing wherein several cmbodimcnts are represented by way of cxample, and wherein Figure 1 is a side elevation of a table-knife showing the bait with the blade attached therein, a part of the bait being'shown in section, and Fig. Zis a cross-section in the plane 2-2 in Fig. 1.. Fig. 3 is a cross-section of a regular hexagonal tang pressed into a circular hole in a haft, Fig. 4 is a like view of a quadrangular tang in an elliptical hole, and Fig. 5 is a like view of a parallelogrammatic tang in an elliptical hole, whereas Fig. 6 is a like view of a round tang in a regular hexagon'al hole. v 1

Referring to'the-drawin and firstly particularly to Figs. 1 and 2, t e plate 11 having in its center a quadrangular hole is attached by soldering or other suitable manner in the upper portion of the metal heft it directly below the constriction i at the head of the blade I). The square tang e is only 'ust so long that its end projects a very litt e out of the plate after it tapered and, compared with the hole in the plate, so large that after the tang has been mechanically forced into the hole like a Wedge, the faces of the tang and hole are pressed against one another with great pressure. As tests have shown, the connection made in this manner can only be broken by an axial tension due to a wei ht of 300 to 400 kilograms. An additions hold of the blade and protection .a ainst its turning in the haft is obtained at t e joint between the bolster k and the upper edge of the haft. Namely the bolster 7c and the end of the haft h plreferably likewise just barely fit one in the ot er and are pressed to ether, Also, in addition, some solder ma e run into the joint between the haft and'tl ie bolster, for the purpose of securing the blade still more firmly,

and in order at the same time to prevent dirt settling in this joint and water penetrating into the metal haft. Also when making the attachment a few dro s of solder can be dropped onto the end 0 the tang before it is pressed into place, but this is by no means necessary for obtaining a firm joint.

In Figs. 3 to 6 a number of other tangs of various shapes are shown ressed into holes in plates in the haft; the s apes of the holes being different from those of their respective tangs, as described above.

It is of no importance if the tang and hole as been pressed into the square e in the same, and the end isslightly owever, be 1l1ed up by some drops of solder which can be applied when the tang is bein pressed into the plate, as already mentions It is to be understood that the tang and hole in the plate, the appertaining )art of the bait can 'be constructed in other like or different forms with-' out departin from the spirit and scope of the invention. .t is also to be understood that although the invention has been described with reference to table-knives, any other 0 erative art of an im lement or tool may e attacher in its meta haft in like manner, without departing from the spirit and scope of the invention.

What I claim as my invention and desire to secure by Letters Patent is:

In a too or implement, the combination with the hollow metal haft having a constriction adjacent its inner end, a plate secured in the haft below the constriction, said plate having a hole therein, the operating part of the tool havin a tang at its end, said tang bein of larger iameter than the hole and force( therein, and a bolster k on the opcrating part of the tool, said bolster being secured-1n the end of the haft above the constriction. I

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

\ HERMANN KRUGER. {In s] Witnesses: I

O'r'ro KoENIe, WALTER EYTHER KAMP.

as well as the bolster ands 

